This chapter first identifies five entry points for science in environmental investment disputes. It continues with analysing framing techniques of both litigants and arbitrators that aim to strategically manage the science-intensity of the legal inquiry. The chapter discusses varied scientific fact-finding methods of investment tribunals. Despite that party-submitted evidence dominates investment arbitration, on rare occasions panels appoint independent experts. As to causal inquiry, the chapter discusses that open causal assessments remain a rarity in arbitral practice, though science-based causal nexus increasingly gains relevance in environmental disputes. As to the standard of review, arbitral tribunals are generally deferential towards the scientific claims of host states. Yet they design different standards to review the scientific basis of host states' risk regulatory measures, for instance, some focus on the transparency of the regulatory process, while others rely on regulatory trends of other states. This chapter concludes with analysing and comparing the various standards of review applied in science-intensive investment arbitral proceedings.